JP3063116B2 - Chemical vapor deposition method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor or electronic component, in which a chemical vapor deposition apparatus (hereinafter, referred to as a CVD apparatus) is used to uniform the film thickness distribution between semiconductor wafers. The present invention relates to a chemical vapor deposition method.

2. Description of the Related Art For example, in a semiconductor manufacturing process, the diameter of a wafer has been increased from 5 inches to 6 inches or 8 inches in parallel with efforts for high integration and miniaturization of devices. 2. Description of the Related Art In recent years, in a batch-type vapor phase epitaxy apparatus using a diffusion furnace having a high throughput, automation of wafer transfer has been advanced in order to cope with an increase in diameter and unmanned wafers. For the purpose of improving productivity and shortening the cleaning time, for example, self-cleaning using chlorine trifluoride gas is being adopted.

Problems to be Solved by the Invention However, the conventional dummy wafer is made of the same material and the same size as the semiconductor wafer, and the wafer has a variation in strength against distortion caused by a heat change and a formed film thickness.

For this reason, when the CVD equipment is automated, if the dummy wafers are used continuously, it is easy to cause troubles in transporting the processed wafers due to damage due to the film formation history, and it is difficult to determine when to replace the dummy wafers by controlling the formal film thickness. In order to remove the formed film, there was a problem that the film had to be taken out of the CVD apparatus and subjected to wet cleaning.

In order to solve this problem, the present invention provides a chemical vapor deposition method using a dummy wafer that is not easily damaged by a change caused by a thermal change and a film thickness.

Another object of the present invention is to provide a chemical vapor deposition method using a dummy wafer capable of performing self-cleaning using chlorine trifluoride gas in removing a formed film.

Means for Solving the Problems A first invention of the present invention is directed to a chemical vapor process comprising forming a semiconductor wafer and a dummy wafer having the same material as the semiconductor wafer and having a greater thickness with respect to the semiconductor wafer. A chemical vapor deposition method, wherein the dummy wafer is used for a film forming process a plurality of times.

According to a second aspect of the present invention, a dummy wafer having a silicon oxide film formed on the surface of the dummy wafer by thermal oxidation or chemical vapor deposition is used, and a gas different from a film forming gas is supplied. 2. The chemical vapor deposition method according to item 1.

According to the first aspect of the present invention, since the thickness is large, breakage due to heat change and distortion caused by the formed film thickness can be reduced.

Further, according to the second aspect of the present invention, since the thickness is large and the silicon oxide film is formed on the surface, self-cleaning using chlorine trifluoride gas is possible.

EXAMPLES Example 1 According to this example, when a silicon nitride film is formed by a CVD apparatus, a dummy wafer (φ6
When the thickness is t = 0.6), the damage occurs in 10 to 15 cycles in the 600 ° treatment, whereas when the thickness is t = 1.1, the thickness is large, so that the strength against the distortion caused by the thermal change and the formed film thickness is low. It has been improved, and 60-70 cycles have been made possible with 600Å processing.

Second Embodiment A difference between the present embodiment and the first embodiment is that a silicon oxide film is formed on the surface of the dummy wafer.

Therefore, according to this embodiment, in addition to the effect obtained in the first embodiment, there is also an effect that self-cleaning using chlorine trifluoride gas can be performed.

Effect of the Invention As described above, according to the first invention, the dummy wafer is thicker than the semiconductor wafer, and therefore, the strength against distortion caused by thermal changes and the formed film thickness is improved. Therefore, when used in a CVD apparatus, it can be expected to reduce transport errors and extend the life of dummy wafers by early replacement.

According to the second aspect of the present invention, the dummy wafer is thicker than the semiconductor wafer and has a silicon oxide film formed on the surface thereof. The film thus formed can be removed by self-cleaning using chlorine trifluoride gas without taking it out of the apparatus. Therefore, a wet cleaning tank is unnecessary, and reduction of manpower spent for cleaning can be expected.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Akihiko Kanayama 1006 Kazuma Kadoma, Kadoma City, Osaka Inside Matsushita Electric Industrial Co., Ltd. (56) References JP-A-58-6136 (JP, A) 112332 (JP, U) Actually open 63-79634 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 21/205 H01L 21/31

Claims (2)

(57) [Claims] 1. A chemical vapor deposition method comprising: forming a semiconductor wafer and a dummy wafer having the same material as the semiconductor wafer and having a greater thickness with respect to the semiconductor wafer; A chemical vapor deposition method for use in film formation. 2. The method according to claim 1, wherein a dummy wafer having a silicon oxide film formed on the surface of the dummy wafer by thermal oxidation or chemical vapor deposition is used, and a gas different from a film forming gas is flowed. Chemical vapor deposition method.